In many applications, semiconductor die are fabricated in the form of modules containing pluralities of semiconductor devices. These modules are then packaged in some desirable form to fit the specific application. To package the modules it is necessary to interconnect the various semiconductor devices and/or die and then connect the devices and/or die to external leads through which the package can be electrically connected into a circuit. The major problem that arises is that the interconnections and connections to external leads generally are formed with wire bonding.
The wire bonding process is slow, expensive and contributes significantly to low yields. As is known in the field, wire bonding machines are very expensive and must be reprogrammed for each different module and/or package that is manufactured. Also, wire bonding machines have a strong tendency to damage semiconductor die as they bond. Wire bonds are easily broken during packaging and, because they must be positioned above the surface of the semiconductor die and/or modules, add substantially to the size of the final package.
As an example, in power packages it is not unusual to have as many as 10-30 devices connected in parallel. Generally each of the devices is a multi-element device requiring a number of connections, or wirebond pads, per device. Also, the power package generally contains some type of controls and/or electronic switch which includes a plurality of connections. A typical power package could include from tens to hundreds of wirebonds, each of which is an opportunity for the wirebonder to damage the semiconductor die. Even if the wirebonding machine parameters for one run are set and optimized, slight variations in force, energy, fixture alignment, cutter residue buildup, or other parameters can create a condition where semiconductor die are damaged.
It would be advantageous from several perspectives to develop a technology that would not require wirebonding.
Accordingly, it is a purpose of the present invention to provide wirebondless module packages.
It is another purpose of the present invention to provide new and improved methods of fabricating module packages to eliminate the necessity for wirebonds.
It is still another purpose of the present invention to provide new and improved wirebondless module packages which are smaller and more rugged than prior packages.
It is still another purpose of the present invention to provide new and improved wirebondless module packages which are manufactured using standard semiconductor processing techniques.
It is a further purpose of the present invention to provide new and improved wirebondless module packages which include a heat sink in the process.